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Suborder: Heteroptera
Hetero- variable Ptera-Wings;
includes true bugs
Sub-order: Homoptera Homo: Alike; Pteron:
Wings (uniform wings)
Jassids, Aphids, mealy bugs, whiteflies,
Planthoppers, Scales etc
Order Hemiptera
Ravy Raaz
Sub order Heteroptera Homoptera
Head Porroct Deflexed
Gula Sclerotized, large Small, membranous or wanting
Rostrum Never extend upto fore coxae Extends between forecoxae
Pronotum Large Small
Trochantin Small Large
Wings Folded flat over abdomen Held like roof over abdomen
Forewings Hemielytra Elytra or thin
Glands Odoriferous glands are present Wax glands are present
Hemiptera is again divided into 2 Sub orders Homoptera and heteroptera
Ravy Raaz
• Suborder: Heteroptera includes true bugs Hetero- variable Ptera-Wings
• Mouthparts piercing and sucking type with slender segmented beak (modified labium)
• usually extends back along the ventral side, sometimes as far as the bases of hind coxae
• There are no palpi
• Pronotum large, the mesonotum exhibits fivefold division and scutellum is prominent
• When winged, the fore wings are basally thickened and membranous apically, Hemelytra
• It has 3 regions i.e. corium, clavus and membrane
• Narrow strip of corium along costal margin is seperated by a suture, embolium
• In a few hemiptera, a cuneus is set off by a suture from the apical part of corium
• Hind wings are entirely membranous and are slightly shorter than forewings
• At rest the wings are held flat on the body
• Alary polymorphism is seen
• Odoriferous glands or repugnatorial glands or scent glands or stink glands are present
• Open near hind coxae on the sides by ventral pores giving out unplesant odour
• Ovipositor small with 2 pairs of valves or well developed to insert eggs in plant tissues
Ravy Raaz
Heteropteran families:
Family: Pentatomidae (Stink bugs or shield bugs)
Broad shield like bugs that produce disagreeable odour
•Scutellum is large triangular extends posteriorly to the extent of covering wings entirely
• In hemelytron, corium large extending to anal margin
• Membrane has many longitudinal veins, from a vein parallel to apical margin of corium
•4 pairs of odoriferous glands are present on dorsum of abdomen of the nymphs
•eggs are barrel shaped with spines on the upper end
Eg: Green (stink) bug – Nezara viridula
Red pumpkin bug -Aspongopus janus
Cabbage painted bug – Bagrada cruciferarum
Ravy Raaz
Family: Lygaeidae Seed bugs or Chinch bugs
Small bugs, hard bodied
• 4 to 5 unbranched simple veins in the membrane
• Cuneus is lacking, clavus is elongate
• Metathoracic gland openings are present
•Front femora moderately swollen with 2 rows of teeth
Eg. Dusky cotton bug –Oxycarenushyalinipennis Groundnut pod bug –Aphanus sorididus
Family: Miridae (Capscidae) Mirid bugs
•Cuneus is present
•Embolium is indistinct
•Majority live on plant juices, some prey on small arthropods
Eg. Calocoris Angustatus-Sorghum ear bug Pachypeltis politus- Betel vine bug Helopeltis antonii- Guava & cashew T mosquito bug Psallus sps. is a predator of thrips Cyrtorhynus lividipennis- Predator on BPH Ravy Raaz
Family: Pyrrhocoreidae (Pyrrhocoreids), red cotton bugs or cotton strainers
• They exhibit red and black colorations
• More branched veins present in hemelytra
• Coxa is rotatory
Eg. Dysdercus cingulatus – red cotton bug
Family : Coreidae Leaf footed bugs long and narrow bugs
• Head narrower, shorter than pronoutm, scutellum smaller
• In hemelytra, richly branched veins are present
• either or both hind femora and tibiae have leaf like dilations
• Metathoracic gland openings present
Eg Rice gundhi bug- Leptocorisa varicornis Pod bugs :Clavigralla gibbosa on pulses
Ravy Raaz
• Characters of the suborder: Homoptera
• Head is deflexed and not generally constricted behind to form a neck
• Mouth parts piercing and sucking type
• Stylets often exceedingly long, retractile, rostrum arising from the back of the head
• In some cases appearing to arise between anterior coxae
• In some adults like male coccids the mouth parts are vestigial or absent
• Pronotum small and collar like
• When winged the four wings are uniform in consistency
• Wings are held roof like over the body at rest
• Alary polymorphism is prevalent
• In male coccids only one pair i.e forewings are present
• Wax glands or honey tubes usually well developed in most of the members
• In most of the species, the life history is very complex involving sexual and
parthenogenetic generations winged and wingless individuals
• In some species, the last nymphal instar Is quiescent and pupa like Ravy Raaz
Family Cicadellidae : (Jassidae) : Jassids or leaf hoppers
• wedge shaped insects usually rest in a position ready for jumping
• One or two rows of small spines are present on hind tibia
• Both young ones and adults running sideward or diagonally
• very important vectors of viral diseases
• Ovipositor adopted for lacerating plant tissues for egg laying
• Many excrete honeydew through anus
• 8. Forewings are thickened and brightly coloured
• Anal veins 1A and 2A do not unite to form ‘Y’ shaped vein
Eg: Cotton leafhopper - Amrasca biguttula biguttula
Paddy leafhopper - Nephotettix virescens
Mango hoppers - Amritodes atkinsoni,Ideoscopus clypealis
Ravy Raaz
Family: Delphacide Plant hoppers
• Most of the species are small with reduced wings
• presence of large mobile apical spur on hind tibiae
• Costal cell is absent in the winged forms
• Alary polymorphism -winged, wingless and brachypterous forms occur
Eg: Brown plant hopper of paddy (BPH)- Nilaparvata lugens
White backed plant hopper on rice (WBPH) -Sogatella furcifera
Ravy Raaz
Family: Aphididae Aphids or plant lice
• small soft bodied, pear shaped, fragile phytophagous insects
• frequently found in large numbers sucking the sap from various parts of plants
• presence of a pair of cornicles on the dorsal surface of 5th or 6th abdominal segments (It is believed that they produce waxy substances)
• Alary polymorphism is prevalent. When winged, hind wings are smaller with fewer veins
• At rest the wings are generally held vertically above the body
• Nine pairs of lateral spiracles present
• Excrete honeydew through anus (honey dew consists of excess sap, excess sugars and waste materials) to which ants are attracted
• Associated phenomenon in reproduction are parthenogenesis, oviparity and viviparity
• Occurrence of alternation of generations
• The sexes are unequally developed, males often being rare
Eg: Myzus persicae – Tobacco aphid
Aphis gossypi – Cotton aphid
Aphis craccivora – Groundnut aphid
Ravy Raaz
Family: Pseudococcidae Mealy bugs
• Females are wingless, elongate oval with distinct segmentation
• Body covered with powdery wax or filamentous waxy secretions
• Legs well developed. No instar is sessile
• Eggs are placed in a loose cottony waxy material
• Eg: Brinjal mealy bug – Planococcus insolitus
Citrus mealy bug - Planococcus citri
• Sugarcane mealy bug - Saccharicoccus sacchari
Ravy Raaz
Family: Coccidae Scale insects (Soft scales)
• Females are flattened, elongate oval insects with obscure segmentation
• hard or smooth exoskeleton or covered with wax or tough scales
• wingless, legs present or absent and the antennae absent or much reduced
• Males are active, 1st pair of wings well developed, 2nd pair reduced to halters
• Metamorphosis complex
• 1st instar nymph has legs & antennae and active known as crawlers
• after 1st moult, become sessile a waxy or scale like covering is secreted
• In males last instar preceeding adult is queicent and called pupa
• Females have one less instar than males
• Excrete honey dew like aphids
Eg: Pulvinaria psidi – Guava scale
Icerya purchasi - cottony cushion scale
Ravy Raaz
Family: Aleurodidae White flies
• resemble tiny moths with opaque body
• wings covered by a fine whitish dust or powdery wax giving white colour
• wing venation is highly reduced
• vasiform orifice opens on basal surface of last abdominal segment in nymphs and adults
• opening is provided with an operculum and beneath it a tongue shaped organ linguae
• The anus opens within the orifice at the base of linguae and Honey dew is excreted
• Metamorphosis is complex
• 1st instar are active but subsequent immature stages are sessile and look like scales
• The scale like covering is a waxy secretion of the insect
• The wings develop internally during metamorphosis and the early instars are larvae
• The next to the last instar is quiescent and is called pupa
• The wings are given out at the moult of last larval instar
• The eggs are with a pedicel, which sometimes exceeds the length of the egg
Eg: Sugarcane whitefly – Aleurolobus barodensis
Cotton whitefly - Bemisia tabaci
Castor whitefly - Trialeurodes ricini
Ravy Raaz